This grant is aimed at facilitating the continued involvement of investigators at the University of minnesota in the multi- institutional cooperative therapeutic and non-therapeutic studies conducted by the Childrens Cancer Study Group (CCSG). During the past five years, the University of Minnesota has maintained its role as a leading institution in CCSG, both logistically and scientifically. Since 1983, there has been a 50% increase in the number of patients placed on study by the University of Minnesota such that by 1987 over 125 patients are expected on study, placing the University of Minnesota second among CCSG's 32 principal institutions. Scientifically, the University of Minnesota investigators have been leaders in various aspects of CCSG studies, including treatment of acute lymphocytic leukemia, acute non- lymphocytic leukemia, and neuroblastoma; investigation of new agents and pharmacokinetics of anti-cancer drugs; bone marrow transplantation for leukemia, neuroblastoma, and other childhood solid tumors; radiation therapy including total body irradiation: characterization of cancer cells, including cytogenetics and cell surface antigen determinations; cancer epidemiology; and studies investigating the late effects of childhood cancer and its treatment. Thirteen University of Minnesota investigators hold 87 positions on CCSG study committees, strategy groups, scientific committees, discipline committees, or administrative committees. Furthermore, these investigators occupy 27 chairpersonships of study committees and strategy groups, placing the University of Minnesota first among the CCSG institutions in scientific leadership. CCSG studies are conducted using a "team approach" which involves individuals from a wide range of disciplines including oncologists, radiation therapists, surgeons, immunologists, pathologists, cytogeneticists, pharmacologists, and epidemiologists. University of Minnesota investigators are involved in virtually all areas of CCSG interest and our involvement in future CCSG studies will continue to grow. This grant requests personnel support for University of Minnesota investigators and personnel key to the maintenance of effective data management and quality control for CCSG studies; travel for University of Minnesota CCSG investigators; and miscellaneous expenses for administering the University of Minnesota's continued involvement in both scientific input and the direction, planning, development, and conduct of clinical investigation and ancillary studies to be conducted by the Childrens Cancer Study Group.